Granite Countertops in kitchen & bathrooms

[Beachboy]

I just noticed that all my granite countertops are supported with 'pressboard' underneath them!? Call me crazy, but isn't having pressboard under these counters a bit stupid? I'd imagine it won't take long for pressboard to start rotting out?

What material do you folks have under your counters to support them?

"You must be the change you want to see in the world."

- Mahatma Gandhi